改进模型的层析成像算法

IMPROVED MODEL FOR COMPUTERIZED TOMOGRAPHY

井间地震层析成像技术能够提供钻孔之间地质体的高分辨图像。LTI法与SIRT法相结合是目前使用较广的一种层析成像算法,在此基础上考虑到一个较好的初始模型能提高算法的准确性及效率性,以及在SIRT算法当中如何分配残差能使反演的结果更好,提出了改进模型的层析成像算法。此方法基于LTI法进行射线追踪得到每个接收点在初始模型上的理论走时后,就利用这个理论走时与实际拾取走时的差值以及射线追踪所得到的射线路径,对初始模型进行修正。通过数值模拟实验发现,该算法的效果较原始算法有一定的提高。

Expressway construction in karst developing area, which need exact information of karst. Cross-well seismic computerized tomography is a geophysical exploration method, which use seismic wave to explore the media between wells, h can provide high reso- lution image of the target. LTI and SIRT are widely used in computerized tomography, improved model method for computerized tomo- graphy whichg based on that. It consider that a better initial model can improve the accuracy and efficiency of the algorithm, and the distribution of residual error in SIRT can also improve the result of inversion. In some degree, the method improve the result by the nu- merical modeling experiment.